Your requirements could not be resolved to an installable set of packages. Problem 1 - Root composer.json requires shopware/administration ^6.6, found shopware/administration[dev-trunk, v6.6.0.0-rc1, 6.6.x-dev (alias of dev-trunk)] but it does not match your minimum-stability. Problem 2 - Root composer.json requires shopware/platform ^6.6, found shopware/platform[dev-trunk, v6.6.0.0-rc1, 6.6.x-dev (alias of dev-trunk)] but it does not match your minimum-stability. Problem 3 - Root composer.json requires shopware/storefront ^6.6, found shopware/storefront[dev-trunk, v6.6.0.0-rc1, 6.6.x-dev (alias of dev-trunk)] but it does not match your minimum-stability.